Memory system in which extension function can easily be set

ABSTRACT

According to one embodiment, a non-transitory medium, a controller, a memory, an extension function section, and an extension register. The controller controls the non-transitory medium. The memory which is serving as a work area is connected to the controller. The extension function section is controlled by the controller. The extension register which is provided on the memory is provided with a certain block length capable of defining an extension function of the extension function section. The controller processes a first command to write header data of a command to operate the extension function section to the extension function section through the extension register, and a second command to read header data of a response from the extension function section through the extension register.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No. 13/560,028 filed Jul. 27, 2012, and is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-147850, filed Jun. 29, 2012, the entire contents of each of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a memory system using, for example, a semiconductor nonvolatile memory.

BACKGROUND

Recently, it is desired that a memory card be not only a mere memory device, but also be a memory device to which various functions can be added in order to impart added value to the memory card. Further, in order to make it possible to use the additional functions on a plug-and-play basis, a general-purpose initialization means is desired.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically showing a memory system applied to an embodiment.

FIG. 2 is a block diagram showing an example of firmware of the memory system shown in FIG. 1.

FIG. 3 is a block diagram showing an example of a read command of an extension register.

FIG. 4 is a timing chart showing a read operation of an extension register to be carried out by a read command.

FIG. 5 is a timing chart showing a read operation of a data port to be carried out by a read command.

FIG. 6 is a block diagram showing an example of a write command of an extension register.

FIGS. 7A, 7B, and 7C are views each showing an operation of a mask register.

FIG. 8 is a timing chart showing a write operation of an extension register to be carried out by a write command.

FIG. 9 is a timing chart showing a write operation of a data port to be carried out by a write command.

FIG. 10 is a view showing an example of a general information field to be set to a first page of an extension register.

FIG. 11 is a flowchart showing an example of an operation of a memory system conforming to a read command.

FIG. 12 is a flowchart showing an example of an operation of a memory system conforming to a write command.

FIG. 13 is a flowchart showing an example of an operation of a host driver.

FIG. 14 is a flowchart showing another example of an operation of a host driver.

FIG. 15 is a view schematically showing an access operation of an extension register in the SDIO.

FIG. 16 is a view showing an example of revision management.

FIG. 17 is a view showing an example of a read command of an extension register according to a second embodiment.

FIG. 18 is a view showing an example of a write command of an extension register according to the second embodiment.

FIG. 19 is a timing chart showing a read operation of an extension register to be carried out by a read command.

FIG. 20 is a timing chart showing a read operation of a data port to be carried out by a read command.

FIG. 21 is a timing chart showing a write operation of an extension register to be carried out by a write command.

FIG. 22 is a timing chart showing a write operation of a data port to be carried out by a write command.

FIG. 23 is a view showing an example of a general information field to be set at a first page of an extension register.

FIG. 24 is a flowchart showing an example of an operation of a memory system conforming to a read command according to the second embodiment.

FIG. 25 is a flowchart showing an example of an operation of a memory system conforming to a write command according to the second embodiment.

FIG. 26 is a view showing an example of a multi-block read command of an extension register according to the second embodiment.

FIG. 27 is a view showing an example of a multi-block write command of an extension register according to the second embodiment.

FIGS. 28A and 28B are views showing an example of a display position of general information according to the second embodiment.

FIG. 29 is a view showing an example of a relationship between the memory space and SDIO space according to the second embodiment.

FIG. 30 is a flowchart shown to explain simplification of initialization of the SDIO according to the second embodiment.

FIG. 31 is a view schematically showing a relationship between a memory device and functional interface of a host according to the second embodiment.

FIG. 32 is a schematic block diagram shown to explain control of a buffer according to the second embodiment.

FIG. 33 is a view showing an example of a function identification code.

FIG. 34 is a view schematically showing a relationship between a host device and memory device according to a third embodiment.

FIG. 35 is a block diagram showing an example of a read command of an extension register according to the third embodiment.

FIG. 36 is a block diagram showing an example of a write command of an extension register according to the third embodiment.

FIGS. 37A, 37B, and 37C are views each showing a pattern of a command.

FIG. 38 is a view showing an example of a data structure of a command header, command payload, response header, and response payload.

FIGS. 39A, 39B, and 39C are views each showing an example of a command header, payload, and response header.

FIGS. 40A, 40B, and 40C are views each showing an example of a command header, payload, and response header.

FIG. 41 is a view showing an example of an “OP Code” of a command header.

FIG. 42 is a view showing an example of an extension register map applied to the third embodiment.

FIG. 43 is a view showing an example of data transfer corresponding to FIG. 37A.

FIG. 44 is a timing chart shown to explain the data transfer shown in FIG. 43.

FIG. 45 is a view showing an example of data transfer corresponding to FIG. 37B.

FIG. 46 is a timing chart shown to explain the data transfer shown in FIG. 45.

FIG. 47 is a view showing an example of data transfer corresponding to FIG. 37C.

FIG. 48 is a timing chart shown to explain data transfer shown in FIG. 47.

FIG. 49 relates to a fourth embodiment, and is a view showing an example of a data structure of a response.

FIG. 50 is a view showing an example of a flag indicating an event of an extension function.

FIG. 51 is a block diagram showing an example of an application and extension function provided in a host device.

FIG. 52 is a sequence chart showing an example of operations of the host device shown in FIG. 51 and a memory device.

FIG. 53 relates to a fifth embodiment, and is a view schematically showing the configuration in which a converter is used.

FIG. 54 is a sequence chart shown to explain an operation of the fifth embodiment.

FIG. 55 is a sequence chart shown to explain another operation of the fifth embodiment.

FIG. 56 is a block diagram showing a modification example of FIG. 53.

DETAILED DESCRIPTION

In general, according to one embodiment, a non-transitory medium, a controller, a memory, an extension function section, and an extension register. The controller controls the non-transitory medium. The memory which is serving as a work area is connected to the controller. The extension function section is controlled by the controller. The extension register which is provided on the memory is provided with a certain block length capable of defining an extension function of the extension function section. The controller processes a first command to write header data of a command to operate the extension function section to the extension function section through the extension register, and a second command to read header data of a response from the extension function section through the extension register.

A schematic explanation of this embodiment is as follows.

(Function Extension Method)

When a host driver looks for a function driver configured to control the additional function, and a corresponding function driver is installed in the host, it becomes possible to easily carry out function extension by adopting a mechanism configured to transfer control to the function driver. Control peculiar to a function is hidden in the function driver, and hence it becomes possible for the host driver to implement an additional function by using only the minimum information. For example, firmware includes an extension register of a plurality of pages managed by the firmware, and provides a standard general information field configured to recognize a specific driver in page 0 of the extension register. Thereby, it becomes possible for the host system to implement the plug-and-play function. Further, by the management carried out by the host system so that each of the functions can be pointed out in order to support the multi-function card/device, it is made possible to use the multi-function card/device without changing the host software.

(Compatibility of SD Memory or SDIO Host Controller)

In the SD memory host controller too, a dedicated command configured to access an extension register by which control of an additional function can be efficiently carried out is defined. By transfer of a fixed-length block of 512 bytes, it is possible to issue the dedicated command from a conventional SD memory host controller. Furthermore, by having information about an effective data length or a masking function at the time of write as an argument of the command, it becomes possible to make the read-modify-write operation unnecessary.

In a host controller compatible with the SDIO card, by making it possible to access the extension register from the SDIO access command, it becomes possible to be compatible with short-length-block transfer and multi-block transfer, and hence it becomes possible to make a further optimized driver.

By supporting a data port serving as a data transfer port, it becomes possible to realize implementation requiring a smaller amount of the extension register space. Further, by using a data port, it becomes possible to efficiently carry out data transfer to a device other than the extension register. It is possible to support a burst transfer command by using a plurality of blocks. Regarding the data port, it is possible to define an arbitrary address of the extension register as a data port when the function is implemented. The card deciphers the address to determine whether the address is associated with a data port or an extension register.

(Definition of Extension Register by Relocatable Address)

By making it possible for the card vendor to assign a register configured to control an additional function to an arbitrary position on the extension register, and by providing address information about the implemented register from the general information field, it is made possible to make the register arrangement relocatable. Accordingly, address arrangement conventionally requiring standardization is made unnecessary, and it becomes easy to manufacture a memory device. Relocation is enabled, and hence it is easily possible, even when a register is extended, to cope with the extension.

Hereinafter, an embodiment will be described with reference to the drawings.

FIG. 1 schematically shows a memory system according to this embodiment.

The memory system is constituted of a memory device 11 such as an SD card, and host 20.

When the memory device 11 is connected to the host 20, the memory device 11 receives power supply to operate, and carries out processing corresponding to access from the host 20. The memory device 11 includes a controller 11 a.

The controller 11 a is constituted of, for example, a host interface 12, CPU 13, read only memory (ROM) 14, random access memory (RAM) 15, buffer 16, and memory interface 17. These are connected to each other by a bus. For example, a NAND flash memory 18, and SDIO 19 serving as an extension function section are connected to the memory interface 17. As the extension function section, for example, a wireless LAN device or the like can be adopted.

The host interface 12 carries out interface processing between the controller 11 a and host 20.

The memory interface 17 carries out interface processing between the controller 11 a and NAND flash memory 18 or the SDIO 19.

The CPU 13 is a unit configured to manage operations of the overall memory device 11. A program configured to control the CPU 13 executes predetermined processing by using firmware (control program and the like) stored in the ROM 14 or by loading the firmware into the RAM 15. That is, the CPU 13 creates various tables and an extension register, to be described later, on the RAM 18, receives a write command, read command or erase command from the host 20 to access an area on the NAND flash memory 18, and controls data transfer processing through the buffer 16.

The ROM 14 stores therein firmware such as a control program to be used by the CPU 13. The RAM 15 is used as a work area of the CPU 13, and stores therein a control program, various tables, and extension register to be described later.

When data sent from the host 20 is to be written to, for example, the NAND flash memory 18, the buffer 16 temporarily stores therein data of a given amount (for example, data of one page) and, when data read from the NAND flash memory 18 is to be sent to the host 20, the buffer 16 temporarily stores therein data of a given amount. Further, the buffer 16 can control the SD bus interface and back-end asynchronously by carrying out the control through the buffer.

The NAND flash memory 18 is constituted of, for example, memory cells of a stacked gate structure or memory cells of a MONOS structure.

The SDIO 19 has a function of a peripheral such as a digital camera and PHS, and function of an interface. By adopting a wireless LAN device as the SDIO 19, it becomes possible for even a digital camera having no wireless communication function to carry out data communication by wireless between itself and an external server, external PC, and the like.

As the host 20, for example, a digital camera, PHS, and the like can be adopted. The host 20 is constituted of a host controller 21, CPU 22, ROM 23, RAM 24 and, for example, hard disk 25 (including an SSD). These are connected to each other by a bus.

The CPU 22 controls the overall host. The ROM 23 stores therein firmware necessary for the operation of the CPU 22. Although the RAM 24 is used as, for example, a work area of the CPU 22, a program which can be executed by the CPU 22 is also loaded here to be executed. The hard disk 25 holds various data items. In the state where the memory device 11 is connected to the host controller 21, the host controller 21 carries out interface processing between itself and the memory device 11. Furthermore, the host controller 21 issues various commands, to be described later, in accordance with instructions from the CPU 22.

(Configuration of Firmware)

FIG. 2 shows an example of the functional configuration of the firmware stored in the ROM 14 of the memory device 11. These functions are realized by the combination of the hardware items such as the CPU 13 and the like constituting the controller 11 a. The firmware is constituted of, for example, a command processing section 14 a, flash memory controller 14 b, extension register processing section 14 c, and function processing program 14 d. When the memory device 11 is activated, the extension register processing section 14 c creates an extension register 31 in the RAM 15. The extension register 31 is a virtual register, and is enabled to define an extension function. In the embodiment, the extension register is not limited to the virtual register. It is possible to provide the extension register as hardware in the CPU 13, for example.

(Configuration of Extension Register)

As shown in FIG. 2, the extension register 31 is constituted of, for example, eight pages. One page is constituted of 512 bytes. In order to access the 512-byte extension register in units of one byte, addresses of at least 9 bits are required and, in order to access the eight pages, addresses of at least 3 bits are required. By the addresses of a total of 12 bits, all the spaces of the extension register are made accessible. Although 512 bytes is an access unit which can be supported by almost all hosts, the access unit is not limited to 512 bytes, and may be made larger than 512 bytes. When the extension register 31 is constituted of an address field of a long bit length, some lower bits are used as an access unit, and remaining upper bits are used to select one of a plurality of pages.

The reason for making the 512 bytes a unit is that the configuration is made in such a manner that a large number of memory card host controllers carry out read/write transfer by using one block (=512 bytes) as a unit. Although a host controller compatible with the SDIO can carry out read/write in units of one byte, not all the host controllers support the above read/write. In order to enable the great majority of the host controllers to control the extension function, it is convenient if access can be carried out in units of 512 bytes.

Of the eight pages (page 0 to page 7), page 0 is an area configured to record a general information field in order to carry out the plug-and-play operation of the extension function. Details of the general information field will be described later. In pages 1 to 7, registers configured to control the extension functions are defined. A position can easily be specified in page 0, and hence page 0 is a suitable place to record the general information field, but the page in which the general information field is to be recorded is not necessarily limited to page 0, and a position in a specific page can be defined as a place configured to describe the general information field.

For read/write of the extension register, dedicated read/write commands to be defined as follows are used. These commands each have a first operation mode in which read/write of the extension register is carried out, and second operation mode in which a data port is configured.

(Read Command (CMD 48) of Extension Register)

FIG. 3 shows an example of the field configuration of a read command (CMD 48) of the extension register. “S” indicates a start bit of the command, “T” is a bit indicating the transfer direction, and “index” indicates the command number. “RS” (register select) indicates a page in the extension register 31, and “OFS” indicates a position (offset from a head of the page) of data in the selected page. By using “RS” of 3 bits, and “OFS” of 9 bits, a space corresponding to the 8 pages of the 512-byte extension register can be specified in units of one byte. More specifically, a read start position in the selected extension register is designated by “RS” and “OFS”.

“LEN” indicates the data length. An effective data length necessary for read in the 512-byte extension register is designated by the 9-bit LEN field.

“CRC7” indicates a cyclic redundancy check code, and “E” indicates an end bit of the command. Further, “rsv” indicates a spare bit.

(Read Command of Extension Register, First Operation Mode)

FIG. 4 shows an example of a read operation of an extension register to be carried out in the first operation mode.

As shown in FIG. 4, upon receipt of a command (CMD 48) from the host 20, the memory device 11 returns a response (R1) to the host 20 and, thereafter reads a 512-byte data block from the extension register 31.

More specifically, by the arguments of the command (CMD 48), i.e., by “RS” and “OFS”, a page in the extension register, and position of data to be read in the page are designated, and data length is designated by “LEN”. In the manner described above, the data in the designated extension register is set to the head of the 512-byte data block, and is read. Among data items in the 512-byte data block, data items having data lengths exceeding a data length specified by “LEN” become ineffective data items. A CRC code is added to the last part of the data block to make it possible to check whether or not the data has been properly received (checking of data is carried out by including ineffective data). Effective data items are arranged from the head, and hence it is not necessary for the host 20 to carry out an operation such as data shift or the like in order to look for effective data.

(Read Command of Extension Register, Second Operation Mode)

FIG. 5 shows an example of an operation of data port read to be carried out in the second operation mode.

Upon receipt of the command (CMD 48), the memory device 11 returns a response (R1) and, thereafter returns the 512-byte data block.

By arguments “RS” and “OFS” of the command, a position in a selected page of the extension register is designated. In FIG. 5, a data port example of a case where the length is “1” is shown. That is, it is sufficient if the data port occupies only an address of one byte on the extension register map. Further, it is sufficient if it is possible to distinguish whether or not an address is a data port by decoding of the address, and it is not necessary for the data to be actually transmitted through the 1-byte width port, and hence the data transmission performance is not adversely affected. It is possible to read data of one block (512-byte unit) from the device assigned to this data port. That is, it is possible to read data of one block (512-byte unit) at one time. The read data is held in, for example, the buffer 16, and is then read by the host 20.

When the same data port is subsequently read, the subsequent 512-byte data can be read. The place from which data to be read from the data port is taken can be freely defined by the specification of the extension function. Regarding data port control, the control can be carried out by defining a control register on, for example, the extension register. A CRC code is added to the last part of the 512-byte data block to make it possible to check whether or not the data has been properly received.

(Write Command (CMD 49) of Extension Register)

FIG. 6 shows an example of a write command of the extension register. In the write command (CMD 49), parts identical to the read command (CMD 48) are denoted by identical reference symbols. The write command and read command are distinguished from each other by “index”. By using “RS” of 3 bits, and “OFS” of 9 bits, a page in the extension register, and position of data in the selected page are designated. A length of data to be written to the 512-byte extension register is designated by a “LEN” field of 9 bits. Accordingly, it is possible to write data of an arbitrary data length (byte unit) within 512 bytes to an arbitrary page and place of the extension register.

The write command (CMD 49) is provided with a mask register in the argument of the command. That is, “Mask” indicates an 8-bit length mask register. By the mask register, it becomes possible to carry out an operation in units of one bit in data write of one byte, and write data to only a specific bit. Accordingly, in a bit operation within one byte, it is not necessary to carry out the read-modify-write operation.

When the data length is one byte, i.e., in the case of “LEN=0” (length 1), the mask register becomes effective. Regarding a bit of the mask register “Mask” having data of “1”, data is written to the bit, and regarding a bit of the mask register “Mask” having data of “0”, the value already set is retained.

That is, when an extension register holding data shown in FIG. 7A is assumed, if data of the mask register is as shown in FIG. 7B, by executing a write command, data is written to a bit of the mask register having data of “1” as shown in FIG. 7C, and in a bit having data of “0”, the original data is retained. Accordingly, it becomes possible to rewrite only the desired bits without carrying out the read-modify-write operation. The parts each indicated by “x” show the bits to which new data is written.

Further, when longer mask data can be supplied by a separate means, even in the case of LEN larger than 1 (LEN>1), although mask write is enabled, in the example shown in FIGS. 7A, 7B, and 7C, mask data is assigned to the command arguments, and hence the 8-bit mask is used.

(Write Command of Extension Register, First Operation Mode)

FIG. 8 shows an example of a write operation of the extension register to be carried out in the first operation mode.

Upon receipt of the command (CMD 49), the memory device 11 returns a response (R1) and, thereafter receives a 512-byte data block.

The memory device 11 returns a CRC code indicating whether or not the data block has properly been received to the host 20. Thereafter, the memory device 11 returns information indicating the busy state until the processing of the command is completed, and notifies the host 20 of the timing at which the host 20 can issue the next command. The data block is held in the buffer 16.

In the command processing, a page and position in the extension register are designated by the arguments “RS” and “OFS” of the command, and data length is designated by “LEN”. Among the data blocks held in the buffer 16, data items each having a length designated by “LEN” are written to the extension register from the head thereof. Data in the data blocks having a length exceeding the data length designated by “LEN” is discarded as ineffective data.

By arranging effective data items from the head of the data block, it becomes unnecessary for the host system to carry out an operation of arranging the effective data items in the middle of the data block.

(Write Command of Extension Register, Second Operation Mode)

FIG. 9 shows an example of an operation of a write data port to be carried out in the second operation mode.

Upon receipt of the command (CMD 49), the memory device 11 returns a response (R1) and, thereafter receives a 512-byte data block.

The memory device 11 returns a CRC code indicating whether or not the data block has properly been received to the host 20. Thereafter, the memory device 11 returns information indicating the busy state until the processing of the command is completed, and notifies the host 20 of the timing at which the host 20 can issue the next command. The data block is held in the buffer 16.

In the command processing, a page and position in the extension register are designated, and a data port is designated by the arguments “RS” and “OFS” of the command. It is sufficient if the data port occupies only an address of one byte on the extension register map. It is possible to write data of one block (512-byte unit) held in the buffer 16 to a certain device assigned to this data port. That is, it is possible to write data of one block at one time.

When the same data port is subsequently written, the subsequent 512-byte data can be written to the device to which the data is assigned. The place to which the data of the data port is delivered can be freely defined by the specification of the extension function. Regarding data port control, the control can be carried out by defining a control register on, for example, the extension register.

(Usage Example of General Information Field)

FIG. 10 shows an example of the general information field shown in page 0 of the extension register 31. By making it possible for the host 20 to specify a driver configured to control the extension function by using the general information field, it is possible for the host system, when an extension function is added, to easily use the extension function, and realize plug-and-play.

A sequence example to be processed by a standard host driver will be described below with reference to FIG. 10.

(Structure Revision)

A structure revision is a revision configured to define the format of page 0 of the extension register 31. When new information is added to the general information field, which version of the general information field is held is indicated by updating the structure revision. The function host driver of the previous version ignores the new field.

(Data Length)

As a data length, the effective data length recorded in page 0 is shown.

(Number of Extension Functions (=N))

The number of extension functions indicates the number of extension functions supported by the device. At the time of start-up, the host driver repetitively checks whether or not drivers for extension functions are installed the number of times corresponding to the number of supported functions.

(Device 1 Function Identification Code)

When a code is set to the device 1 function identification code, it is indicated that the standard driver can be used. When the OS supports the standard driver, the device can be used without installing a dedicated driver. When a dedicated driver is installed, the dedicated driver is preferentially used. In the case of a nonstandard function, “0” is set to this field. In this case, this function is controlled by only a dedicated driver.

(Device 1 Manufacturer Identification Information, Device 1 Function Identification Information)

Each of the device 1 manufacturer identification information, and device 1 function identification information is information configured to specify a dedicated driver and, in these fields, a name of the manufacturer, and name of the distributor or identification information of the extension function are described by using, for example, an ASCII character string. On the basis of these information items, the host driver checks whether or not a dedicated driver of the device 1 is installed.

As the function identification information, a model number of the device, revision, and the like are described by using, for example, an ASCII character string.

(Beginning Address of Next Device)

The beginning address of the next device indicates an address in page 0 in which device information of the next device is described. When the host system does not support this device, this device cannot be used, and hence the next device is checked. The fields after this are of a variable length, and hence definition is set to this position.

(Device 1 Address Pointers 1 to X, Length Fields 1 to X)

The device 1 address pointers 1 to X, and length fields 1 to X indicate that a plurality of extension register areas can be defined for one function. The addresses and lengths are enumerated below. The length field may not necessarily be required information and this field can be omitted.

(Device 1 Address Pointer 1 (Start Address), Length 1)

The first area of the extension register used by the device 1, beginning address in the space of pages 1 to 7 of the extension register, and size of the used extension register area are indicated.

That is, one or a plurality of extension register areas can be assigned to one device, and the address pointer indicates a place (start address) of an arbitrary extension area other than page 0. The length indicates a size for occupying the extension register having the pointer at the beginning address.

(Device 1 Address Pointer 2 (Start Address), Length 2)

A position and area size of the second area in the extension register assigned to the device 1 are indicated. Thereby, an application in which, for example, the standard driver carries out control in only the first area, and a dedicated driver is enabled to efficiently carry out control by using the first area and second area is enabled.

(Device 1 Address Pointer X (Start Address), Length X)

A position and area size of the Xth area assigned to the device 1 are indicated.

As described above, a plurality of areas can be defined in the extension register. The areas are arranged in such a manner that they do not overlap each other. It is possible to check whether or not there is overlap between the areas by using the length information.

When an additional field becomes necessary, the additional field is additionally defined after this. A host which cannot recognize a new field reads the recognizable fields, and ignores the additional field. A skip can be carried out by using the above-mentioned (beginning address of the next device) field.

(Operation of Read Command (CMD 48))

FIG. 11 shows an operation of the controller 11 a in the memory device 11 compatible with the read command (CMD 48).

When the read command is received, the arguments “RS” and “OFS” of the command are analyzed by the CPU 13, and it is determined whether or not the read command is read from the data port (ST11). That is, a page “RS” in the extension register, and position of data in the page are determined. As a result, when it is determined that the read command is read from the extension register, data having a data length “LEN” is acquired from a position indicated by “OFS” in the selected page of the extension register 31 (ST12). The acquired data is set to the buffer 16 (ST13).

On the other hand, when it is determined in step ST11 that the read command is read from the data port, data of 512 bytes is acquired, in the second operation mode, from a specific function of, for example, the SDIO 19 through a data port of a position indicated by “OFS” of the selected page of the extension register 31 (ST14). The acquired data is set to the buffer 16 (ST15).

(Operation of Write Command (CMD 49))

FIG. 12 shows an operation of the controller in the memory device 11 compatible with the write command (CMD 49).

When the write command is received, the arguments “RS” and “OFS” of the command are analyzed by the CPU 13 (command processing section 14 a), and it is determined whether or not the write command is write to a data port (ST21). That is, a page “RS” in the extension register, and position of data in the page are determined. When it is determined, as a result, that the write command is write to a part other than the data port, it is determined whether or not the argument “LEN” of the command is 0 (“LEN”=0) (length 1), i.e., whether or not the mask is effective (ST22). When it is determined, as a result of the determination, that “LEN” is not 0 (length is greater than 1), write processing of the extension register is carried out by the extension register processing section 14 c. That is, data of a length designated by “LEN” is acquired from the buffer 16 (ST23). The acquired data is set to a position designated by “OFS” in the page of the extension register selected by “RS”.

On the other hand, when it is determined in step ST22 that “LEN” is 0 (“LEN=O”) (length is 1), and the mask is effective, data of 1 byte, and a mask of 1 byte are acquired from the buffer 16 by the extension register processing section 14 c (ST25). By using the 1-byte data, and 1-byte mask, a mask operation shown in FIGS. 7A, 7B, and 7C is executed, and part of the data of the position designated by “OFS” in the page of the extension register selected by “RS” is rewritten (ST26).

Further, when it is determined in step ST21 that the write command is write to the data port, data of 512 bytes is acquired from the buffer 16 (ST27). The acquired data is transferred to a specific function of, for example, the SDIO 19 through a data port of the position indicated by “OFS” in the selected page of the extension register 31 (ST28).

(Host Driver Processing)

FIG. 13 shows processing of the host 20. When the memory device 11 is connected to the host 20, the memory device 11 is activated, and extension register 31 is spread on the RAM 15 of the memory device 11. The host device 11 first issues a read command (CMD 48) by using the host driver, and acquires data of page 0 of the extension register 31 (ST31). Then, the structure revision of the acquired page 0 is confirmed, and it is further confirmed which version of the general information field is held (ST32). After this, the number of supported functions N, and beginning address of the device information are acquired (ST33, ST34).

Subsequently, it is checked, by a search, whether or not a dedicated function driver corresponding to the acquired extension function is installed in the host 20 (ST35, ST36). When there is no dedicated function driver as a result of the checking, it is further determined whether or not the function identification code described in page 0 of the extension register is “0” (ST37). As a result, when the function identification code is “0”, the extension function is not supported, and hence it is recognized that this device cannot be used, whereby the processing is shifted to a search for a driver for the next device (ST34).

Further, as a result of the determination of step ST37, when the function identification code is not “0”, the standard function driver installed in the host 20 is searched for (ST38, ST39). As a result, when there is no standard function driver, this extension function is not supported, and hence it is recognized that the device cannot be used, whereby the processing is shifted to a search for a driver for the next device (ST34).

Further, as a result of the search of steps ST35, and ST36, when there is a standard function driver, and as a result of the search of steps ST35, and ST36, when there is a dedicated function driver, an address of the device, and length number described in page 0 are acquired (ST40). This operation is executed the number of times corresponding to the number of the addresses and lengths (ST41).

After this, the retrieved dedicated function driver or the standard function driver is loaded from, for example, the hard disk 25 of the host 20 into the RAM 24, an address pointer (start address) of one or a plurality of extension areas described in page 0 is delivered to the function driver, and an extension function is initialized (ST42). The address and length information is delivered when the function driver loaded into the RAM 24 is executed. Although there is the possibility of the standard function driver, and dedicated function driver differing from each other in the number of deliverable address and length information items, the information items are delivered by the number of the deliverable items in the order registered in page 0. Accordingly, the firstly registered address and length area serves as a common function register, and address and length area registered later can fill a role of an option.

Initialization is carried out by the function driver. That is, on the basis of the start address delivered from the host driver, the function driver accesses the extension register to which the function is assigned to initialize the device. In the initialization operation, it is necessary to consider the power consumption of the device. This is because the device must be used within the range of power which can be supplied by the host. When the device has a plurality of power modes, it is necessary to select a power mode lower than the device power which can be supplied by the host. The host system transmits the power which can be supplied by the host system to the function driver by a separate means, whereby selection of the power mode is enabled.

The operation of above steps ST34 to ST43 is repeated until the number of supported functions N is reached (ST43).

It should be noted that when, for example, a new field is added to page 0, processing of the new field is added to a part between step ST40 and step ST41. A host driver which cannot recognize the new field is configured to skip the field.

As described above, the host 20 acquires the information of page 0 of the extension register 31 and, on the basis of the information, retrieves the driver, whereby plug-and-play can be realized. Further, unlike in the conventional case, the device vendor can define a function at an arbitrary position in the extension register without the need for determining the fixing position of the extension register, and hence function extension can easily be implemented.

FIG. 14 shows a modification example of FIG. 13, parts identical to FIG. 13 are denoted by identical reference symbols, and only different parts will be described below.

In FIG. 14, the dedicated function driver, and standard function driver are different from each other in the search processing. That is, in step ST34, after the beginning address of the device information is acquired, first, it is determined whether or not the function identification code is “0” (ST51). As a result of the determination, when the function identification code is not “0”, i.e., when the function is the standard function, it is further determined whether or not a dedicated driver is to be used (ST53). As a result of the determination, when the dedicated driver is not used, a standard function driver is searched for (ST54, ST55). When there is no standard function driver as a result of the search or when it is determined in step ST53 that the dedicated function driver is used, the dedicated function driver is searched for (ST52, ST56). When there is the dedicated function driver as a result of the search or when there is the standard function driver in step ST55, the address and length number is acquired as described previously (ST40).

By the above operation too, it is possible to realize plug-and-play as in the case of FIG. 13.

It should be noted that in the above description, it has been described that the extension function driver is installed in the host 20, and searches the inside of the host 20. However, the configuration is not limited to this, and the extension function driver may also be stored in the memory card 11. In this case, the memory card 11 is also made the search object of the extension function driver.

FIG. 33 shows information for specifying function drivers when a card has options and the function drivers differ according to the options. As shown in FIG. 33, a function identification code indicates two kinds of information, an option code and a function code. The function code indicates a standardized specific functional specification, and the kind of option is also defined by the functional specification. The option code is information which indicates whether an option implemented in the card affects the function driver. This example shows the information on whether CMD48/49 are supported and the information on whether CMD52/53 are supported. When the option code is 1 byte, the driver using CMD48/49 is denoted by “01h” (“h” indicates a hexadecimal number), and the driver using CMD52/53 is denoted by “02h”. When installing the function driver in a host system, these codes are registered as a functional driver implementing code. The host system with which two drivers are installed has the both option codes “01h” and “02h”.

In a card designed in order to use CMD48/49, “01h” is indicated in the option code. The host system selects a driver for CMD48/49 based on the option code. Moreover, In a card designed in order to use CMD52/53, “02h” is indicated in the option code. The host system selects a driver for CMD52/53 based on the option code.

It is important that the host driver does not need to have the information about the options, and a general-purpose host driver can be made. The information about the options is given to the host system when a function driver is installed. Since a host driver does not need for the information about the options, the host driver does not need to update a host driver when a new card is installed. The function specification can decide contents of the options freely, and by installing two or more function drivers corresponding to the combination of the options in the host system, the optimal function driver can be selected according to the support state of the card.

(Access to Extension Register in SDIO)

FIG. 15 shows access to the extension register in the SDIO.

A host controller compatible with the SD memory card can access the extension register by using commands CMD 48 and CMD 49, and control the extension function. That is, the host controller supports the fixed-length block transfer and single-block transfer.

On the other hand, a host controller compatible with the SDIO card is enabled to access the extension register by using the commands CMD 48 and CMD 49, and the extension register is mapped onto each function area of the SDIO, whereby it becomes possible for the host controller to access the extension register also from the SDIO commands CMD 52 (write command), and CMD 53 (data transfer command). By using the SDIO commands, it is possible to support the variable block length transfer, and multi-block transfer, and optimize the driver. When access is made by using the commands CMD 48 and CMD 49, it is possible to access the extension register without regard to the spatial mapping of the SDIO.

More specifically, when the extension register is used in the SDIO, each page of the extension register is mapped onto each function area. In the case of the example shown in FIG. 15, page 0 of the extension register is mapped onto the function 0 of the function area 61, page 1 and page 2 are mapped onto the function 1, and page 3 is mapped onto the function 2. The function 0 holds address information indicating positions on the SDIO map at which function registers of the pages are arranged. Accordingly, by using the address information, it is possible to access each page of the extension register by means of not only the driver using the commands CMD 48 and CMD 49, but also the driver using the commands CMD 52 and CMD 53.

It should be noted that the host 20 delivers position information about the extension register assigned to the extension function to the driver from the general information field described in the first page of the extension register. Thereby, it becomes possible to control the extension function even when the extension function is arranged at an arbitrary position.

Further, in the state where data transfer is enabled between the host 20 and memory device 11 by the plug-and-play, it becomes possible to carry out data transfer between the host 20 and SDIO serving as an extension function section by using the commands CMD 48, CMD 49, CMD 52, and CMD 53.

According to the above embodiment, the extension register including a plurality of pages is provided in the RAM 15 of the memory device 11, and the standard general information field configured to recognize a specific driver is set in page 0 of the extension register 31. Accordingly, the host 20 sets a driver by referring to the general information field in page 0 of the extension register 31, whereby plug-and-play can be realized.

Further, by defining the commands CMD 48 and CMD 49 exclusively used to access the extension register, the host controller for the memory can also efficiently control the added function.

Moreover, the data transfer is made transfer of the 512-byte fixed block length, and hence the dedicated command configured to access the extension register can be issued from the conventional host controller for the memory.

Furthermore, information about the effective data length or a masking function at the time of write is set as an argument of the command, and hence when part of the data is to be rewritten, the read-modify-write operation is not necessary, and part of the data can easily be rewritten.

Further, the host controller compatible with the SDIO card supports the data port, and hence it becomes possible to carry out data transfer to a certain specific device, and realize implementation that enables reduction in the amount of the extension register space consumed.

Further, by using the data port, it is possible to support a burst transfer command based on a plurality of blocks in the SDIO, and efficiently carry out data transfer of a device other than the memory. (Although not described in this embodiment, in the memory too, when a burst transfer command based on a plurality of blocks is defined, transfer of a plurality of blocks is enabled.)

Furthermore, it becomes possible for the host controller compatible with the SDIO card to be compatible with short-length-block transfer, and multi-block transfer by accessing the extension register by using an access command of the SDIO. Accordingly, it becomes possible to create a further optimized driver.

Further, it is made possible for the card vendor to assign a register configured to control an additional function to an arbitrary position on the extension register, and thus the card vendor provides address information about the implemented register from the general information field in page 0. Accordingly, it is possible to arrange the defined function registers in a relocatable manner. Accordingly, the work of determining address assignment conventionally requiring standardization is made unnecessary, and it is possible to facilitate manufacture of the device.

It should be noted that the configuration of the extension register is not limited to a plurality of pages, and it is also possible to make the extension register constituted of one page, and set areas corresponding to page 0, and pages 1 to 7 within the one page.

(Determination of Usable Functions by Revision Confirmation)

Each of the functions described above is provided with a register configured to indicate revision on the extension register set defined by the function. Further, the function driver knows the corresponding revision by itself. When a certain function is to be extended by revision improvement, it is possible to maintain the compatibility by extending the function while maintaining compatibility with the conventional function. When a removable card is used, usable functions are determined by the combination of the function revision of the card, and revision of the function driver installed in the host system.

FIG. 16 shows an example of revision management. FIG. 16 shows examples of the function available in accordance with the revision of each of the card and function driver. For example, the case where there are three revisions (A<B<C) will be described. In this case, extension in which C includes the function of B, and B includes the function of A is carried out. Revision management is carried out by the function driver. The function driver itself knows its own revision. Available functions are determined on the basis of the combinations shown in FIG. 16. In all the function driver revisions, the function of the revision A can be used and, in order to use the function of the revision B, it is necessary for the function driver revision to be higher than or equal to B.

Second Embodiment

FIG. 17 and FIG. 18 each show an example of the field configuration of a read command CMD 48, and write command CMD 49 according to a second embodiment. It should be noted that in FIG. 17, and FIG. 18, parts identical to FIG. 3, and FIG. 6 are denoted by identical reference symbols, and a description of them is omitted.

The commands CMD 48 and CMD 49 shown in FIG. 17 and FIG. 18 are the commands CMD 48 and CMD 49 shown in FIG. 3 and FIG. 6 in each of which the address field constituted of 12 bits of “RS” and “OFS” is extended to 20 bits constituted of “FNO” and “Addr” to thereby consider the affinity/compatibility to/with the SDIO.

The “MIO” field is a bit separating the memory space and SDIO space from each other, thereby enabling both the spaces to define an extension register independently of each other. Accordingly, when the extension register is defined, it is possible to prevent both the spaces from interfering with each other. When “MIO” is 0 (“MIO”=0), the extension register for the memory can be accessed and, when “MIO” is 1 (“MIO”=1), extension register for the SDIO can be accessed.

The “FNO/FID” field is set to one of “FNO” and “FID” according to the value of the “MIO” field. When “MIO” is 1 (“MIO”=1), “FNO” is a 3-bit field indicating a function number and, when “MIO” is 0 (“MIO”=0), “FID” is a 4-bit field indicating function identification information. Due to the different bit numbers, different symbols are used for expression. When the aforementioned general information field is to be read, “FNO/FID” is set to 0 (“FNO/FID”=0). It is sufficient if the host driver sets this field to 0. Although “FID” is not used in the memory space, “FNO” is used in the SDIO space to distinguish the eight function spaces.

That is, regarding “FNO/FID” (4 bits), when “MIO” is 1 (“MIO”=1), the bits 38 to 36 indicate “FNO”, and bit 35 is always made “0”.

Further, regarding “FNO/FID”, when “MIO” is 0 (“MIO”=0), the bits 38 to 36 indicate “FID”. “FID” is used to distinguish the functions without increasing the memory space.

(The memory space may be increased by using “FID”, this being not limited.)

When a function is to be implemented in a card, a unique value is assigned to “FID/FNO”, and is indicated in the field definition of general information as will be described later. Accordingly, when a command is issued to the data port, the function driver sets “FID/FNO” as an argument, whereby it is possible for the card to confirm that the command is a command corresponding to the designated function. Accordingly, it is possible to prevent data corruption and malfunction due to designation of a wrong data port, and erroneous write from occurring, thereby assuring safety.

Although when the host attempts to specify a function from address information, the host must decode the address information, function distinction is enabled by using only “FID/FNO”, and control of the host driver can be simplified. That is, the same command is used by a plurality of functions in a mixing manner, and hence in the host and card, “FID/FNO” is set so that the functions can be distinguished.

The “Addr” field (17 bits) is an address, and can access a space of 128 KB. The upper 8 bits of “Addr” are used as a page number. One of pages 0 to 7 is selected by the 8 bits. A 512-byte block in the selected page is accessed by the lower 9 bits. That is, by using “MIO”, “FNO” (“MIO”=1), and “Addr”, a position of the extension register is designated.

The “Len” field (8 bits) shown in FIG. 17 indicates an effective data length.

Further, in the write command (CMD 49) shown in FIG. 18, “MW” is a bit used to designate the mask write mode. When “MW” is 0 (“MW”=0), the mask is disabled and, when “MW” is 1 (“MW”=1), the mask is enabled.

Further, in the “Len/Mask” field, when the mask is disabled (“MW”=0), the data length is set to 9 bits (16 to 08). Further, when the mask is enabled (“MW”=1), the data length is set to 1, and the write operation is controlled as described above by the lower 8 bits of the 9 bits (16 to 08). That is, when each bit in the 8 bits is “1”, data of the register is written and, when each bit is “0”, the bit in the register is not changed, and the value set already is maintained.

In the second embodiment, it is possible to make the space which can be accessed by the SDIO commands CMD 52 and CMD 53, and SDIO space which can be accessed by the commands CMD 48 and CMD 49 coincide with each other. That is, it becomes possible to access the same extension register set by using either commands.

(Read Command of Extension Register, First Operation Mode)

FIG. 19 shows an example of a read operation of the extension register to be carried out in a first operation mode of a read command (CMD 48) of the extension register.

As shown in FIG. 19, upon receipt of a command (CMD 48) from the host 20, the memory device 11 returns a response (R1) to the host 20 and, thereafter reads a 512-byte data block from the extension register 31.

More specifically, a position of data in the page to be read is designated by “FNO” (MIO=1) and “Addr”, and effective data length to be read is designated by “Len”. In this way, the data in the designated extension register is set to the head of the 512-byte data block, and is then read. Of the 512-byte data block, data exceeding the data length designated by “Len” becomes ineffective data. A CRC code is added to the end of the data block, thereby making it possible to check whether or not the data has been properly received (checking of data is carried out by including ineffective data).

FIG. 20 shows an example of a read operation of a data port to be carried out in the second operation mode.

Upon receipt of the command (CMD 48), the memory device 11 returns a response (R1) and, thereafter returns the 512-byte data block.

The memory device 11 verifies whether or not the argument “FID/FNO” of the command coincides with the assigned extension register set. The extension register set is specified by “FNO” (“MIO”=1) and “Addr”. When “FID/FNO” and the extension register set coincide with each other, a position in the selected page of the extension register is designated by the argument “Addr” of the command. It is sufficient if the data port occupies only an address of one byte on the extension register map. It is sufficient if it is distinguished whether or not an address is a data port by decoding of the address, and it is not necessary for the data to be actually transmitted through the 1-byte width port, and hence the data transmission performance is not adversely affected. It is possible to read data of one block (512-byte unit) from the device assigned to this data port. That is, it is possible to read data of one block (512-byte unit) at one time. The read data is held in, for example, the buffer 16, and is then read by the host 20.

When the same data port is subsequently read, the subsequent 512-byte data can be read. The place from which data to be read from the data port is taken can be freely defined by the specification of the extension function. Regarding data port control, the control can be carried out by defining a control register on, for example, the extension register. A CRC code is added to the last part of the 512-byte data block to make it possible to check whether or not the data has been properly received.

Further, as a result of the above verification, when “FID/FNO” is not coincident with the value assigned to the function, the data transfer operation is not executed, and the data block is not transferred.

(Write Command of Extension Register, First Operation Mode)

FIG. 21 shows an example of a write command of the extension register.

Upon receipt of the command (CMD 49), the memory device 11 returns a response (R1) and, thereafter receives a 512-byte data block.

The memory device 11 returns a CRC code indicating whether or not the data block has properly been received to the host 20. Thereafter, the memory device 11 returns information indicating the busy state until the processing of the command is completed, and notifies the host 20 of the timing at which the host 20 can issue the next command. The data block is held in the buffer 16.

In the write command (CMD 49), parts identical to the read command (CMD 48) are denoted by identical reference symbols. The write command, and read command are distinguished from each other by “Index”. A page in the extension register, and a position of data in the selected page are designated by “FNO” (“MIO”=1), and “Addr” of 17 bits. Furthermore, a data length to be written to the 512-byte extension register is designated by the 9-bit “Len” field. Accordingly, it is possible to write data having an arbitrary data length (byte unit) within 512 bytes to an arbitrary page and position in the extension register.

As described above, in the write command (CMD 49), a mask register is provided in the argument of the command. That is, “Mask” indicates an 8-bit length mask register. By the mask register, it becomes possible to carry out an operation in units of one bit in data write of one byte, and write data to only a specific bit. Accordingly, in a bit operation within one byte, it is not necessary to carry out the read-modify-write operation. When the data length is one byte, i.e., when the upper 1 bit of “Mask” is “1”, the mask register becomes effective.

(Write Command of Extension Register, Second Operation Mode)

FIG. 22 shows an example of an operation of a write data port to be carried out in the second operation mode. Upon receipt of the command (CMD 49), the memory device 11 returns a response (R1). Thereafter, the memory device 11 verifies whether or not the argument “FID/FNO” of the command coincides with the extension register set. The extension register set is specified by “FNO” (“MIO”=1) and “Addr”. When “FID/FNO” and the extension register set coincide with each other, a position in the selected page of the extension register is designated by the argument “Addr” of the command, and the 512-byte data block is received.

Subsequently, the memory device 11 returns a CRC code indicating whether or not the data block has properly been received to the host. Thereafter, the memory device 11 returns information indicating the busy state until the processing of the command is completed, and notifies the host 20 of the timing at which the host 20 can issue the next command. The data block is held in the buffer 16.

In the command processing, a page and position in the extension register are designated, and a data port is designated by the argument “Addr” of the command. It is sufficient if the data port occupies only an address of one byte on the extension register map. It is possible to write data of one block (512-byte unit) held in the buffer 16 to a certain device assigned to this data port. That is, it is possible to write data of one block at one time.

When the same data port is subsequently written, the subsequent 512-byte data can be written to the device to which the data is assigned. The place to which the data of the data port is delivered can be freely defined by the specification of the extension function. Regarding data port control, the control can be carried out by defining a control register on, for example, the extension register.

Further, as a result of the above verification, when “FID/FNO” is not coincident with the value assigned to the function, the data transfer operation is not executed, and the data block is discarded.

(Usage Example of General Information Field)

FIG. 23 is a view showing an example associated with designation of FID according to the second embodiment. The meaning of the general information field is identical to FIG. 10. The point different from FIG. 10 is that a 4-bit field is secured in order to set the value of “FID/FNO” in the format of the extension address, and length field. Unique “FID/FNO” is set for each function. Each function implemented in the card knows its own “FID/FNO”.

(Operation of Read Command (CMD 48))

FIG. 24 shows an operation of a controller 11 a in the memory device 11 corresponding to the read command (CMD 48) shown in FIG. 19 and FIG. 20.

When the read command is received, it is verified by the CPU 13 whether or not the argument “FID/FNO” of the command coincides with the assigned extension register set (ST51). The extension register set is specified by “FNO” (“MIO”=1) and “Addr”. As a result of the verification, when both of them coincide with each other, the argument “Addr” of the command is analyzed, and it is determined whether or not the read command is read from the data port (ST52). That is, it is determined whether or not the address is an address defined by “FNO” (“MIO”=1) and “Addr” as the data port.

As a result, when it is determined that the address is not the address of the data port, and the command is read of the extension register, data of the data length “Len” is acquired from the selected page of the extension register 31 on the basis of the position “Addr” in the first operation mode (ST53). The acquired data of the data length “Len” is set to the 512-byte data block of the buffer 16 (ST54).

On the other hand, when it is determined in step ST52 that the read command is read from the data port, data of 512 bytes is acquired from, for example, a specific function of the SDIO 19 through a data port of a position set in advance in the selected page of the extension register in the second operation mode (ST55). The acquired data is set to the 512-byte data block of the buffer 16 (ST56).

As a result of the determination of step ST51 described above, when the command is not a command associated with the data port, the processing is terminated.

(Operation of Write Command (CMD 49))

FIG. 25 shows an operation of a controller in the memory device 11 corresponding to the write command (CMD 49).

When the write command is received, it is verified by the CPU 13 (command processing section 14 a) whether or not the argument “FID/FNO” of the command coincides with the assigned extension register set (ST61). The extension register set is specified by “FNO” (“MIO”=1) and “Addr”. As a result of the verification, when both of them coincide with each other, the argument “Addr” of the command is analyzed, and it is determined whether or not the write command is write to the data port (ST62). That is, it is determined whether or not the position is a position of the data port set in advance by “FNO” (“MIo”=1) and “Addr”.

As a result of the above determination, when it is determined that the write command is write to a part other than the data port, it is determined whether or not the argument “MW” of the command is “1”, i.e., whether or not the write is mask write (ST63).

As a result of the determination, when it is determined that the write is not mask write, write processing of the extension register is carried out by the extension register processing section 14 c. That is, data of a length designated by “Len” is acquired from the data block of the buffer 16 (ST64). The acquired data is set to a designated position in the selected page of the extension register on the basis of “Addr” (ST65).

On the other hand, when it is determined in step ST63 that “MW” is “1” (“MW″=”1″), and the write is mask write, 1-byte data is acquired from the data block of the buffer 16 by the extension register processing section 14 c, and 1-byte mask is acquired from the argument (ST66).

Subsequently, a mask operation shown in FIGS. 7A, 7B, and 7C is executed by using the 1-byte data, and 1-byte mask, and data obtained when the mask operation of the 1 byte is executed is set to a predetermined position in a predetermined page of the extension register designated by “Addr” (ST67).

Further, when it is determined in step ST62 that the write command is write to the data port, 512-byte data is acquired from the data block of the buffer 16 (ST68). The acquired data is sent to, for example, a specific function of the SDIO 19 through a data port of a position in a designated page of the extension register (ST69).

As a result of the determination of step ST61 described above, when the write command is not a command associated with the data port, the processing is terminated.

(CMD 58, CMD 59)

FIG. 26 and FIG. 27 each show a multi-block transfer command configured to improve transfer efficiency of data, FIG. 26 shows multi-block read (CMD 58), and FIG. 27 shows multi-block write (CMD 59).

Although the arguments of the commands CMD 58 and CMD 59 are similar to those of the commands CMD 48 and CMD 49, they partly differ from each other in the definition. Further, the command CMD 58 has no argument “Len” of the command CMD 48, and command CMD 59 has no arguments “MW” and “Len/Mask” of the command CMD 49. This is because transfer to a data port is assumed in the multi-block transfer. The commands CMD 58 and CMD 59 are optional commands, and a data port is configured in such a manner that a plurality of single-block transfer commands CMD 48 or CMD 49 can be substituted for the command CMD 58 or CMD 59.

Data transfer through a data port is assumed in the multi-block transfer. Accordingly, this command becomes effective only when an address of this command coincides with an address defined as a data port in the extension register space. Accordingly, when this command is executed with respect to a normal extension register, an error occurs, and data transfer is not executed.

A code configured to recognize a function for which an issued command is used is set to the “FID/FNO” field (4 bits). Accordingly, by using the “FID” field, the function can be recognized by means of the value, and implementation is facilitated. The function can also be recognized by using the “Addr” (address) field. However, an address to be assigned differs depending on the card, and hence there is the problem that it is difficult for the host driver to manage recognition of a function from an address.

It is possible for the host driver to use a data buffer or the like implemented in the host system for each function for switching control.

The arguments of the command CMD 58/59 do not include the “Len” field configured to designate the data length. This is because for data transfer of long data, it is necessary to designate a long block count, and this information is too much for the argument of the read/write command to designate. Accordingly, it is necessary to designate the block count necessary for data transfer before issuing the command CMD 58/59. Accordingly, for example, a method of defining a register configured to set a block count to the extension register, and setting the register by using the command CMD 49, a method of issuing a command configured to set a block count immediately before the command CMD 58/59 is issued or the like is used.

When setting the number of blocks to the extension register, “FID/FNO” of CMD 49 which sets it up, and “FID/FNO” of CMD 58/59 which executes data transfer need to be in coincidence. The data transfer is not performed when both of these are not in coincidence.

When data is set to the extension register, the data can independently be set for each function, and each function is not affected by other functions. When a common block count command is used, setting of a block count to the memory multi-block command, and distinction thereof are required. Accordingly, it is necessary to issue the command immediately before issuing each command CMD 58/59, and it is necessary for the host driver to manage the issuing order in such a manner that other commands are not issued immediately after issuance of the command.

In order that the host may specify a function of a multi-function card/device, a relative card address (RCA) obtained by initialization, device ID, aforementioned “MIO” information, and “FNO/FID” information are needed.

Each of FIGS. 28A and 28B shows example of a display position of a general information field according to the second embodiment. In the memory space shown in FIG. 28A, the general information field is arranged in page 0 of the extension register and, in the SDIO space shown in FIG. 28B, the general information field is arranged at a specific position at which the field does not conflict with the conventional register. In FIG. 28B, for example, the general information for SDIO is arranged at “008FFh”-“00800h” (512 bytes) (“h” indicates a hexadecimal number).

FIG. 29 shows an example of the correspondence between the memory space and SDIO space according to the second embodiment. In FIG. 29, parts identical to FIG. 15 are denoted by identical reference symbols.

The memory extension register can be accessed by using the command CMD 48/49. More specifically, single-block transfer is carried out by using a fixed-block length of 512 bytes. Furthermore, in the case of the data port, it is possible to carry out multi-block transfer by using the command CMD 58/59. The SDIO extension register can be accessed not only by the command CMD 48/49 but also by the command CMD 52/53. The command CMD 53 is a variable-length command, and hence can be used for access to the SDIO extension register irrespective of the data port.

(Installation of Function Driver)

Whether or not the SDIO function (CMD 52/53) can be used is determined by the function supported by the host system. A host that does not support the SDIO installs a function driver using the commands CMD 48/49 and CMD 58/59. A host system that supports the SDIO can further install a function driver using the command CMD 52/53.

It should be noted that the command CMD 53 is a command which supports, for example, variable-length block transfer and multi-block transfer, and can be read or written, and command CMD 52 is a command which has, for example, no data, and enables read or write of 1-byte data by argument and response.

The SDIO extension register space of the command CMD 48/49 is equivalent to the space of the command CMD 52/53. The command CMD 53 supports variable-length block transfer and multi-block transfer, and hence by using an optimized SDIO driver, data transfer is executed more efficiently.

Like a host supporting the command CMD 48/49 refers to the information without referring to the card information structure (CIS), the general information of the SDIO can be seen from a specific position of the function 0.

(Selection of Function Driver)

Regarding an SDIO-compatible card, when a function driver using the command CMD 52/53 is installed, the function driver is used and, when the function driver is not installed, a function driver using the commands CMD 48/49, and CMD 58/59 is used.

Regarding an SDIO-incompatible card, a function driver using the commands CMD 48/49, and CMD 58/59 is used.

(Initialization Operation of SDIO)

FIG. 30 schematically shows a second initialization operation of the SDIO in a combo card.

Heretofore, the definition of the initialization sequence (a first initialization operation) of the SDIO is given in such a manner that the SDIO function is not enabled unless an SDIO initialization command (CMD 5) is firstly executed. Accordingly, even when a memory is used in the combo card, re-initialization is required when the SDIO is to be used, thereby making it hard for the host to use the specification.

Normally, it is desirable that an I/O function be initialized immediately before the function is used in order not to waste the system resources or not to waste the power. Regarding the timing for initialization of the function, it is recommendable to carry out the initialization at a point of time at which the application using the function is activated.

Further, in the re-initialization, changes in the relative card address (RCA) are made, and hence the accessing method of the memory is affected. In order to enable the SDIO function without affecting memory control, it is desirable that the memory initialization sequence be made the fundamental, and the SDIO function be made addable later.

Thus, as shown in FIG. 30, when the memory device 11 is activated and initialized (ST71), a command (CMD 3) is issued, and relative card address (RCA) is acquired (ST72). After this, a command (CMD 7) is issued (ST73), and the memory device 11 is set to a transfer state, i.e., a state where the memory can be used (ST74). Then, a common resource of cards, such as a pass mode and a power consumption setup, is set up (ST75). In this state, an initialization command (CMD 5) of the SDIO is issued (ST76). Thereby, the SDIO is initialized, and reception of the commands CMD 52 and CMD 53 is enabled (ST77).

In step ST76, it is also possible to set up a common resource of the SDIO automatically. Conventionally, a memory and I/O had the independent setting method in order to control a common resource. For this reason, drivers contained in a memory and I/O needed to be adjusted similarly. In the second initialization operation, a card which received CMD5 copies the common resource of the memory set up in ST75 to I/O. Therefore, it is not necessary to adjust each driver. The common resource contains a bus speed mode, RCA, current limit/power Limit, and a setup of drive capability, etc., for example.

This is an addition to the initialization method, and initialization can also be carried out by the conventional SDIO initialization sequence, and the conventional sequence has compatibility.

According to the above-mentioned configuration, the function is initialized at the timing at which the application using the function is activated, and hence it is possible to initialize each function without affecting the memory control.

(Function Driver Interface)

Heretofore, the SDIO has been controlled by assigning necessary control bits to the common register. In order for a card to control by setting a value to a register, the card needs to implement a processing function. When carrying out specific processing, by calling a functional driver, it becomes possible to process by a function driver instead of processing inside a card. More specifically, the process is performed by a host.

When the control which has conventionally been carried out by the card through the common register is defined as an application program interface (API) of the function driver, it is possible to form the control into software. By standardizing the API level, implementation of the card can be facilitated.

Examples of the API are shown below.

(1) Initialize Function

Calling a function from the host driver to initial the function

(2) Abort/Reset Function

Abort or reset of a function

(3) Get Function Information

Read of function revision

Read of function information (support information or the like)

Read of interrupt information (polling)

(4) Power Consumption Control

Power mode information implemented in the function

(5) Power Off Notification

Notifying the timing at which power shutdown is allowed

(6) Application Interface

Control interface with the application

Particularly, in a card in which a plurality of functions are implemented, when the power of the card is turned off, it is necessary for the host to turn off the power after each function is brought into a state where each function allows power shutdown. Power Off Notification is an API used for this control.

FIG. 31 schematically shows a relationship between an SD card serving as the memory device 11, and function interface of the host 20.

The host 20 is constituted of a host controller 21, host driver 71, file system 72, memory application 73, function driver 74, and function application 75. Further, the SD card serving as the memory device 11 includes an extension register 31, and function hardware 19 constituted of, for example, the SDIO.

In the host 20, the host driver 71 supports a function of detecting and loading the function driver 74. That is, the host driver 71 refers to the general information field of the extension register to detect the function driver 74, and executes the function driver, whereby the host driver 71 can use the extension function. Further, the function driver 74 configured to control the extension register 31, and function application 75 communicate with each other by means of an API defined by the functional specification.

The SD card includes the aforementioned general information field for the purpose of standardization so that the extension register 31 defined by the functional specification, and host driver 71 can find and load the function driver 74.

The host controller 21, and memory device 11 communicate with each other by using the aforementioned command CMD 48/49 or the like.

According to the configuration described above, by defining the control which has conventionally been carried out in the card as the API of the function driver, it is possible to form the control into software. Further, by standardizing the API level, implementation of the card can be facilitated.

Further, the host driver 71 refers to the general information field of the extension register to detect the function driver 74, and execute the function driver, whereby the host driver 71 can use the extension function. Accordingly, the host 20 can easily use the extension function.

(Control of Data Buffer by “FID”)

It is possible for the memory device 11 to determine for which function a command is intended by recognizing address information. However, the address range differs depending on the function, and hence it is difficult for the host 20 to recognize a function from the address.

Accordingly, as described above, it is possible for the host 20 to easily recognize the function by using “FID/FNO”.

Further, it is possible to control, for example, a plurality of buffers of the host 20 by using “FID/FNO”.

As shown in FIG. 32, the host 20 includes buffers 81 and 82 to be used when the host 20 carries out data transfer with respect to a plurality of functions of an SD card serving as the memory device 11, the buffers independently corresponding to the functions. These buffers 81 and 82 are connected to the host controller 21 through a multiplexer (MUX) 83. The buffers 81 and 82 and the multiplexer 83 are constituted by virtual components, and the buffers 81 and 82 are configured on the system memory, and a function of the multiplexer 83 is realized by a software by a driver. An address of buffers selected by the multiplexer 83 is supplied to the host controller. By controlling the multiplexer 83 by means of “FID/FNO”, it is possible to select a buffer 81 or 82 corresponding to each function.

That is, the host 20 can select a corresponding buffer 81 or 82 in accordance with “FID/FNO” set to the command CMD 58/59 by using the multiplexer 83.

When, for example, a read command CMD 58 has been issued from the host controller 21, data read from an extension register of the corresponding function of the memory device 11 is supplied to the multiplexer 83 through the host controller 21. The multiplexer 83 supplies the received data to one of the buffers 81 and 82 on the basis of “FID/FNO”.

Further, when, for example, a write command CMD 59 is issued from the host controller 21, the multiplexer 83 supplies data selected from one of the buffers 81 and 82 to the host controller 21 on the basis of “FID/FNO”, and host controller 21 transfers the data to the memory device 11. The memory device 11 supplies the data to an extension register of the corresponding function on the basis of “FID/FNO”.

As described above, “FID/FNO” is used to control the multiplexer 83, whereby it is possible to surely select the buffer 82 or 83 corresponding to each function.

Third Embodiment

As described above, it is made possible to provide an extension register in the SD card as a memory device, and write data to the extension register or read data from the extension register by using a command CMD48, CMD49, CMD58 or CMD59.

In a third embodiment, a specific method of transferring a necessary command or a message from a host device 20 to an extension function section 19 or transferring a response from the extension function section 19 to the host device 20 will be described.

In the third embodiment, a command and response necessary for an operation of the extension function are defined, and a place for delivery and receipt of the command and response is also determined. Furthermore, when long data is to be transferred between the host device 20 and extension function section 19, for example, data called a command payload is added to define the method of transferring the data as the need arises.

FIG. 34 is a view showing the third embodiment, and schematically shows a relationship between the host device 20 and an SD card serving as a memory device 11 on the firmware level. In FIG. 34, parts identical to FIG. 1 are denoted by identical reference symbols.

The host device 20 includes an extension function application 20-1, and card command issuance section 20-2.

The memory device 11 includes a controller 11 a, NAND flash memory 18, and extension function section 19. The controller 11 a includes a card command controller 11-1, extension register 31, and memory controller 11-2.

When transmission/reception of data such as a command, message or the like is carried out between the host device 20 and extension function section 19 of the memory device 11, the card command issuance section 20-2 issues one of CMD48, CMD49, CMD58, and CMD59, a command header 20 a, response header 20 c and, as the need arises, a command payload 20 b, and response payload 20 d.

That is, when data is transferred from the host device 20 to the memory device 11, the command header 20 a and, as the need arises, the command payload are used. The command header 20 a is supplied to the memory device 11 by using CMD49, and the command payload 20 b is supplied to the memory device 11 by using CMD59.

On the other hand, when a response from the extension function of the memory device 11 is received by the host device 20, the response header 20 c and, as the need arises, the response payload 20 d are used. The response header 20 c is received by using CMD48, and the response payload 20 d is received by using CMD58 (multi-block read).

(Command CMD58, CMD59)

FIG. 35 shows CMD58 serving as a read command, and FIG. 36 shows CMD59 serving as a write command. In FIG. 34 and FIG. 35, an argument of CMD58/59 is similar to FIG. 26 and FIG. 27. Accordingly, only parts different from FIG. 26 and FIG. 27 will be described below.

In the case of the example shown in FIG. 26 or FIG. 27, when long data is to be transferred, immediately before issuance of CMD58/59, CMD23 used to set the block number has been issued.

Conversely, in the third embodiment, CMD58/59 enables long data to be transferred without using CMD23.

In FIG. 35 and FIG. 36, parts different from FIG. 26 and FIG. 27 are arguments “BUS” (block unit select) and “BUC” (block unit count). “FNO” is substantially identical to “FID/FNO”, and is used to distinguish a memory space selected by “MIO” or a functional space in an SDIO section.

“BUS” is a field used to specify a size of a block unit. In the case of “BUS″=”0″, the block unit size is 512 bytes and, in the case of “BUS″=”1″, the block unit size is 32 Kbytes. Here, 32 Kbytes indicate that 64 block data (64×512 bytes) is treated as one block unit.

“BUC” is a field used to specify the block unit number. As the block unit size to be specified by this field, the overall size of data items to be calculated by using the block unit size specified by “BUS”, and transferred is calculated. However, the block used as the unit of the data size at the time of data transfer is fixed at 512 bytes irrespectively of BUS.

Further, as will be described later, a port of the extension register is specified by an address specified by “ADDR” (address field).

(Transmission/Reception Pattern of Commands)

FIGS. 37A, 37B, and 37C show patterns of commands to be subjected to transmission/reception between the host device 20 and memory device 11. As the transmission/reception patterns of commands, there are, for example, three types.

Type 1 shown in FIG. 37A shows a case where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49, and a response header from the memory device 11 is received by the host device 20 by using CMD48.

The type 1 pattern is suitable for transmission/reception of short data.

Type 2 shown in FIG. 37B shows a case where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49, thereafter a command payload 20 b is transmitted from the host device 20 to the memory device 11 by using CMD59 and, then a response header 20 c from the memory device 11 is received by the host device 20 by using CMD48.

The order of transmission of the command header 20 a, and transmission of the command payload 20 b is not limited to the above. The command payload 20 b may be transmitted first and, subsequently the command header 20 a may be transmitted.

The type 2 pattern is suitable for a case where data longer than 512 bytes is transmitted to the extension function.

Type 3 shown in FIG. 37C shows a case where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49, thereafter a response header 20 c from the memory device 11 is received by the host device 20 by using CMD48 and, then a response payload 20 d from the memory device 11 is received by the host device 20 by using CMD58.

Here, the order of reception of the response header 20 c, and reception of the response payload 20 d is not limited to this. The response payload 20 d may be received first and, then the response header 20 c may be received.

The type 3 pattern is suitable for a case where data longer than 512 bytes is received from the extension function.

Whether or not a command payload 20 b or a response payload 20 d is necessary is specified by the command header 20 a as will be described later.

FIG. 38 shows an example of a data structure of a command header 20 a, command payload 20 b, response header 20 c, and response payload 20 d.

The command header 20 a is constituted of 512 bytes, and includes, for example, an “operation code (OP Code)”, “rsv”, “argument length”, “payload length”, “argument”, and “padding”. In the data structure of the command header 20 a, contents of the “argument” are changed depending on the contents of the “OP Code” as will be described later.

The “OP Code” indicates a code of a command used to operate the extension function. Furthermore, as will be described later, whether or not a command payload 20 b or a response payload 20 d is necessary is specified in the “OP Code”.

The “argument length” indicates a data length of the “argument”, and the “payload length” indicates a data length of the payload.

The “padding” is data used to make the length of a command header identical to the data transfer processing unit (512 bytes) and, the data itself has no meaning. The “padding” of the command payload 20 b, response header 20 c or response payload 20 d is similar to the “padding” of the command header 20 a.

The command payload 20 b has a data length of 512 bytes×N (N is a natural number equal to or greater than 1), and this data length is managed by the payload length of the command header 20 a. The command payload 20 b is constituted of, for example, a “command payload” treated as actual data, and “padding”. The contents of the “command payload” change according to the “OP Code”.

For example, when the “OP Code” indicates processing of writing data to the NAND flash memory 18 through the extension function section 19, the command payload is the write data.

Further, when the extension function section 19 has an authentication processing function and, if the “OP Code” indicates write of data of an encrypted key block, the “command payload” becomes data of the encrypted key block.

The response header 20 c is constituted of 512 bytes. The response header 20 c includes, for example, a “response code”, “response data length”, “response data”, and “padding”.

The response payload 20 d is constituted of a “response payload”, and “padding”. The contents of the “response payload” change according to the contents of the response. When the response is a result of reading data of the NAND flash memory through the extension function, the contents of the “response payload” are the read data.

(Example of Command Header, Payload, and Response Header)

FIGS. 39A, 39B, and 39C and FIGS. 40A, 40B, and 40C each show an example of the command header, payload, and response header.

FIGS. 39A, 39B, and 39C show an example of a case where the extension function has a function of processing an encryption key used in the authentication processing of the memory device 11.

For a case where data called an encrypted key block (EKB) used in the authentication processing of the memory device 11 is to be written to the memory device 11, an example of transmitting a command called “write EKB” in order to write an EKB to the memory device is shown.

FIG. 39A shows an example of the command header 20 a of this case.

“OP Code” is “80h”, and indicates a “write EKB” command.

“Reserved” is set to adjust the data position for the purpose of future extension, and for facilitation of data processing carried out by a device.

“Argument Length” indicates the length of the argument of the command and, in this example, “04h” is set.

“Payload Length” indicates the length of the payload, and “N” is set.

From “Block Number” to “Padding data” are treated as arguments. “Block Number” indicates the number of an EKB to be recorded and, “n” is an identification number used to identify one of a plurality of EKBs.

“Reserved” and “Padding data” are as described previously.

FIG. 39B shows an example of a command payload 20 b in this example. In the case of “write EKB”, the EKB data itself is transferred as the “command payload”. The length of the command payload 20 b is specified by above-mentioned “Payload Length” of the command header 20 a. The memory device 11 is notified by the command header 20 a of the “payload length” before receiving the command payload 20 b, whereby the memory device 11 can carry out advance preparations for recording.

FIG. 39C shows an example of the response header 20 c in this example. In the case of “write EKB”, the response header 20 c is constituted of “Response Code” and “Padding data”. A write processing result of the EKB data is shown in “Response Code”. For example, when the write is successful, “00h” is set as “Response Code”.

FIGS. 40A, 40B, and 40C show an example of transmitting a command called “Read EKB” to be used when the extension function reads EKB data used in the authentication processing of the memory device 11 from the memory device 11.

FIG. 40A is a view showing an example of the command header 20 a of this case. The meanings of “OP Code”, “Reserved”, “Argument Length”, and “Payload Length” are identical to the case of “Write EKB” shown in FIGS. 39A, 39B, and 39C.

“OP Code” is “81h”, and indicates the “read EKB” command.

“Argument Length” is, in this case, set at “0Ch”.

As “Payload Length”, “N” is set.

From “Block Number” to “Padding data” are treated as arguments. “Block Number” indicates the number “n” of the recorded EKB.

“EKB Offset” indicates a read start address of the EKB to be read.

“EKB Length” indicates a length of the EKB to be read.

FIG. 40B shows an example of the response payload 20 b of this case. In the case of “Read EKB”, the response payload 20 b transfers EKB data read from the extension function section 19 to the host device 20 on the basis of “Block Number”, “EKB Offset”, and “EKB Length” specified by the command header 20 a. Accordingly, the “Response Payload” is the EKB data itself.

The response header 20 c of the case of “read EKB” is constituted of “Response Code” and “Padding data”. A read processing result is shown in “Response Code”. For example, when the read processing is successful, “00h” is set.

Although, in this example, “Response Data” has not been used, when EKB data is to be transferred, data transfer can be carried out by recording digest data of the EKB data into the “Response Data”. As the digest data, for example, a hash function SHAI or the like of the cryptogram can be utilized, and it is possible to transfer data from the memory device 11 to the host device 20 with the memory data transfer and calculation processing value separated from each other.

FIG. 41 shows an example of “OP Code” of the command header 20 a.

Regarding “OP Code”, it is possible to assign processing commands of the extension function in sequence from 1. Further, it is also possible to assign a bit indicating presence/absence of the command payload 20 b or the response payload 20 d to the inside of “OP Code”.

In FIG. 41, the sixth bit of the “OP Code” is called, for example, the “command payload bit”, and is a bit indicating whether or not a command payload is necessary. When the “command payload bit” is “1”, this command indicates that the command payload is transmitted.

Further, when the “command payload bit” is “0”, this command indicates that the command payload is not transmitted, and only the command header executes the command processing.

The fifth bit of the “OP Code” is called the “response payload bit”, and is a bit indicating whether or not a response payload is necessary. When the “response payload bit” is “1”, this command indicates that the memory device transmits a response payload.

Further, when the “response payload bit” is “0”, it is indicated that the memory device does not transmit a response payload, and transmits only a response header as an execution result of the command processing.

FIG. 42 shows an example of a map of the extension register 31 applied to the third embodiment. In this map, Offset indicates a relative address from the beginning address, and this Offset is specified by the “ADDR” field of CMD58 or CMD59.

Offset “4” indicates a register called the “Extension Register Status”. This “Extension Register Status” is a read-only register indicating that the extension register is in the idle state, transmission state or in the reception state.

Offset “8” indicates a register called the “Extension Register Operation”. This “Extension Register Operation” is a writable register or a readable register to be used by using CMD58 or CMD59. This register is made resettable.

Offset “12” is a register called the “Extension Command Port”, and is a write-only port of the extension command.

Offset “13” is a register called the “Extension Command Payload Port”, and is a write-only port of the command payload.

Offset “14” is a register called the “Extension Response Payload Port”, and is a read-only port of the extension response payload.

Offset “15” is a register called the “Extension Response Port”, and is a read-only port of the extension response.

(Transaction Data (Type 1))

FIG. 43 shows the transaction data of a case of type 1 where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49 shown in FIG. 37A, and a response header from the memory device 11 is received by the host device 20 by using CMD48.

When CMD49 is issued from the host device 20, and the command header 20 a is transferred, a page and position in the extension register are specified by the “Addr” of CMD49 shown in FIG. 18, and the “Extension Command Port” is further specified. An OP Code or the like is transferred to the extension function section 19 through this “Extension Command Port”.

Further, when CMD48 is issued by the host device 20, a page and position in the extension register are specified by the “Addr” of CMD49 shown in FIG. 17, and the “Extension Response Port” is further specified. A response header 20 c is read from the extension function section 19 through this “Extension Response Port”, and is transferred to the host device 20.

FIG. 44 shows a timing chart of the transaction data (type 1).

As shown in FIG. 44, upon receipt of CMD49, the memory device 11 returns a response R1 and, thereafter receives a command header 20 a as a 512-byte data block.

The memory device 11 returns a CRC code indicating whether or not the command header 20 a has correctly been received to the host device 20. Thereafter, the memory device 11 returns busy signals until the command processing described in the command header 20 a is completed, and notifies the host device 20 of the timing at which the host device 20 can issue a next command. The command header 20 a is held in a buffer 16.

In the command processing, a page and position in the extension register are specified by the argument “Addr” of CMD49, and the “Extension Command Port” serving as a data port is further specified. The command header of one block (512 bytes) held in the buffer 16 is written to an assigned device of the extension function section 19 through this “Extension Command Port”.

After this, upon receipt of CMD48, the memory device 11 returns a response R1.

In the command processing, the memory device 11 specifies a page and position in the extension register by the argument “Addr” of CMD49, and the “Extension Response Port” serving as a data port is then specified. A response header 20 c treated as a 512-byte data block is read from an assigned device of the extension function section 19 through this “Extension Response Port”. The read response header 20 c is transferred to the host device 20.

(Transaction Data (Type 2))

FIG. 45 shows the transaction data of a case of type 2 where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49 shown in FIG. 37B and, thereafter a command payload 20 b is transmitted by using CMD59, a response header is read from the memory device 11 by using CMD48, and then the read response header is received by the host device 20.

Like in the case of type 1, when CMD49 is issued by the host device 20, and the command header 20 a is transferred, a page and position in the extension register are specified by “Addr” of CMD49, and the “Extension Command Port” is further specified. An OP code or the like is transferred to the extension function section 19 through this “Extension Command Port”.

Subsequently, CMD59 is issued by the host device 20, a command payload 20 b is transferred to the memory device 11, and a plurality of payload blocks are transferred to the extension function section 19 through the “Extension Command Payload Port” of the extension register.

After this, when CMD48 is issued by the host device 20, a response header 20 c is read from the extension function section 19 through the “Extension Response Port” of the extension register, and is then transferred to the host device 20.

FIG. 46 shows a timing chart of the transaction data (type 2).

As shown in FIG. 46, upon receipt of CMD49, the memory device 11 returns a response R1 and, thereafter receives a 512-byte command header 20 a.

The memory device 11 returns a CRC code indicating whether or not the command header 20 a has correctly been received to the host device 20. Thereafter, the memory device 11 returns busy signals until the command processing described in the command header 20 a is completed, and notifies the host device 20 of the timing at which the host device 20 can issue a next command. The command header 20 a is held in the buffer 16. The command processing is identical to the transaction data (type 1), and hence a description thereof is omitted.

Subsequently, upon receipt of CMD59, the memory device 11 returns a response R1.

In the command processing, the memory device 11 specifies a page and position in the extension register by the argument “ADDR” of CMD59, and the “Extension Command Payload Port” serving as a data port is then specified. A response header 20 c treated as a 512-byte data block constituting the command payload 20 b is written to an assigned device of the extension function section 19 through this “Extension Command Payload Port”.

More specifically, the memory device 11 first receives one block data of a size (512 bytes/32 Kbytes) specified by “BUS” of CMD59. Subsequently, the memory device 11 returns a CRC code indicating whether or not the 512-byte data has correctly been received to the host device 20, and outputs busy signals until the data reception processing is completed.

After this, the above operations are repeated until reception of data of a block number specified by “BUC” of CMD59 is completed.

It should be noted that the data transmitted to the memory device 11 by the command payload 20 b is held in the buffer 16. Accordingly, it is possible for the memory device 11 to transfer the data held in the buffer 16 to the extension function section 19 in units of one block without the control of the host device 20, and so-called direct memory access (DMA) transfer is enabled.

After this, upon receipt of CMD48, the memory device 11 returns a response R1 and, thereafter the host device 20 receives a response header 20 c formed as a 512-byte data block through the “Extension Response Port”. The command processing is identical to the transaction data (type 1), and hence a description thereof is omitted.

(Transaction data (type 3))

FIG. 47 shows the transaction data of a case of type 3 where a command header 20 a is transmitted from the host device 20 to the memory device 11 by using CMD49 shown in FIG. 37C, thereafter a response header is read from the memory device 11 by using CMD48, the response header is received by the host device 20 and, subsequently a response payload 20 b is received by using CMD58.

As in the case of the transaction data (type 1) or (type 2), when CMD49 is issued by the host, and the command header 20 a is transferred, a page and position in the extension register are specified by “Addr” of CMD49, and the “Extension Command Port” is further specified in the memory device 11. A command header 20 a is transferred to the extension function section 19 through this “Extension Command Port”.

Subsequently, when CMD58 is issued by the host device 20, a response payload 20 d is read from the extension function through the “Extension response Payload Port” of the extension register, and is transferred to the host device 20.

After this, when CMD48 is issued by the host device 20, a response header 20 c is read from the extension function through the “Extension Response Port” of the extension register, and is transferred to the host device 20.

FIG. 48 shows a timing chart of the transaction data (type 3).

As shown in FIG. 48, upon receipt of CMD49, the memory device 11 returns a response R1 and, after this, receives a 512-byte command header 20 a.

The memory device 11 returns a CRC code indicating whether or not the command header 20 a has correctly been received to the host device 20. Thereafter, the memory device 11 returns busy signals until the command processing described in the command header 20 a is completed, and notifies the host device 20 of the timing at which the host device 20 can issue a next command. The command header 20 a is held in the buffer 16. The command processing is identical to the transaction data (type 1), and hence a description thereof is omitted.

Subsequently, upon receipt of CMD58, the memory device 11 returns a response R1 and, thereafter receives 512-byte data constituting a response payload 20 d.

In the command processing, the memory device 11 specifies the “Extension Response Payload Port” on the basis of “ADDR” of CMD58, and receives one block data of a size (512 bytes/32 Kbytes) specified by “BUS” of CMD58 from the extension function section 19 through this “Extension Response Payload Port”. The received data is transferred to the host device 20. Subsequently, the memory device 11 transmits a CRC code indicating whether or not the 512-byte data has correctly been received to the host device 20.

After this, the above operations are repeated until reception of data of a block number specified by “BUC” of CMD58 is completed.

After this, upon receipt of CMD48, the memory device 11 returns a response R1 and, thereafter the host device 20 receives a response header 20 c formed as a 512-byte data block through the “Extension Response Port”. The command processing is identical to the transaction data (type 1), and hence a description thereof is omitted.

It should be noted that although, in the description of the transaction data (type 2), the command header 20 a is transferred earlier than the command payload 20 b, the command header 20 a may be transferred after transmitting the command payload 20 b.

Further, although, in the description of the transaction data (type 3), the response header 20 c is transferred after the response payload 20 d, the response payload 20 d may be transferred after transferring the response header 20 c.

According to the third embodiment described above, data transmission/reception to be carried out between the host device 20 and memory device 11 is separated into that based on CMD48/49/58/59, that based on the command header, and response header, and that based on the command payload, and response payload. Accordingly, after command processing, it is possible to carry out preparation for transfer of data to be transferred by the next command payload 20 b to the extension function section 19 on the basis of the command header 20 a. Therefore, it is possible to efficiently transfer data arriving by the command payload, to the extension function section 19. Therefore, for example, it is possible to transfer, by DMA, data which has arrived by the command payload.

Further, the response is separated into that based on the response header 20 c, and that based on the response payload 20 d. Accordingly, after the command processing, and after carrying out preparation for the response on the basis of the response header 20 c, it becomes possible to efficiently transfer data arriving from the extension function section 19 to the host device 20 as the response payload 20 d.

Further, the host device 20 transfers the command header 20 a including an OP code and argument specifying the operation of the extension function section 19 to the extension function section 19 through the extension command port of the extension register by using CMD49 and, thereafter receives the response header 20 c including the response code and response data, and supplied from the extension function section 19 through the extension response port of the extension register by using CMD48. Accordingly, it is possible to transfer a command or a message necessary for the extension function section 19, and transfer a response from the extension function section 19 to the host device 20.

Further, when long data is to be transferred to the extension register, it is possible to transfer a command payload 20 b constituted of a plurality of blocks to the extension function section 19 through the extension command payload port of the extension register by using CMD59, and read a response payload including long data constituted of a plurality of blocks through the extension response payload port of the extension register by using CMD58. Therefore, it is possible to write or read long data to or from the extension function section 19.

Moreover, CMD58/59 includes “BUS” specifying a block size serving as an argument, and “BUC” specifying the block number. Accordingly, it is not necessary to use CMD23 specifying the block number, and hence it is possible to easily transfer long data.

Fourth Embodiment

In the first to third embodiments, upon receipt of CMD48/49, the memory device 11 returns a response R1 to the host device 20.

However, the extension function section 19 inside the memory device 11 has not been provided with means for notifying the host device 20 of events such as completion of processing of a command, error, and the like. Although it is possible to display these events through the extension register, it is necessary for the host device 20 to check whether or not an event has occurred by polling, this being inefficient.

Thus, in a fourth embodiment, a flag notifying an event in the extension register is provided in a response R1 to be returned in response to each of all the commands including a command to access the extension register, thereby making it possible to notify the host device 20 of an event without the host device 20 accessing the extension register.

FIG. 49 shows an example of the data structure of the response R1. The response R1 is constituted of, for example, 32 bits. Of these bits, for example, the eighteenth bit is set as a flag, i.e., extension function event (EF_EVENT) indicating an event of the extension function.

When an event occurs in, for example, at least one of a plurality of extension functions in the memory card 11, the flag EF_EVENT is set to “1”. The bit of the flag EF_EVENT may be returned to “0” at a subsequent response or may be returned to “0” when the flag to be described next is read.

FIG. 50 shows an example of an extension function event flag provided in, for example, the extension register.

This extension function event flag is constituted of, for example, 17 bits, and numbers of extension functions are arranged in one-to-one correspondence with the bits.

When an event occurs in an extension function, the bit of the number of the corresponding extension function is set to “1”. The type of the event may be defined so that the event can be notified to the inside of the extension register. This bit may be returned to “0” when the value of the bit is read or timing at which the bit is returned to “0” may be defined for each extension function.

FIG. 51 shows an example of a case where the host device 20 is provided with an application, extension function application 1, extension function application 2 and, further a file system, extension function driver 1, and extension function driver 2 respectively corresponding to the former three applications. An operation to be carried out by a host device 20 configured as described above when the memory device 11 is accessed by the host device 20 will be described below.

FIG. 52 shows an example of a sequence chart of an operation to be carried out when the memory device 11 is accessed by the host device 20 configured as described above.

First, when a write request or a read request occurs in the application or the file system of the host device 20 (S81), CMDXX is created from the card driver or the host controller (S82). This CMDXX is one of CMD48/49/58/59.

Upon receipt of CMDXX, the memory device 11 returns a response R1 to the host device 20 (S83).

When the flag EF_EVENT included in the response R1 is set to “1”, the card driver or the host controller issues CMD48 (S84). Upon receipt of a response R1 (S85), the card driver or the host controller reads the extension function event flag of the extension register (S86).

The extension function event flag is analyzed by the card driver or the host controller and, for example, when it is detected that an event has occurred in the extension function driver 1, the extension function driver 1 is notified of the occurrence of the event by an interrupt or polling of the card driver (S87).

After this, the extension function driver 1 issues CMD48 to the card driver or the host controller in order for it to read the contents of the event (S88), and the card driver or the host controller issues CMD48 to the memory device 11 (S89).

Upon receipt of CMD48, the memory device 11 returns a response R1 to the host device 20 (S90).

After this, the contents of the event are transferred from the extension function section to the host device 20 by the command processing (S91). The contents of the event are further transferred to the extension function driver 1 (S92).

According to the fourth embodiment described above, the flag EF_EVENT indicating that an event has occurred in one of the extension functions is provided in the response R1 of CMD48/49/58/59. Accordingly, the host device can learn that an event has occurred in one of the extension functions by receiving the response R1. Therefore, it is not necessary to detect occurrence of an event by polling, and hence it is possible to efficiently detect an event.

Further, the extension function event flag is provided in the extension register, and it is made possible by the extension function event flag to determine that an event has occurred in one of the functions of the extension function section 19. Therefore, it is possible for the host device 20, when occurrence of an event is detected by the flag EF_EVENT, to easily identify an extension function in which the event has occurred by reading the extension function event flag.

Fifth Embodiment

In each of the first to fourth embodiments, a case where the extension function of the memory device 11 is accessed by the host device 20 has been described.

Conversely, in a fifth embodiment, a case where a conversion device is provided between a host device 20 and memory device 11, and an extension function of the memory device 11 is accessed through this conversion device will be described below. More specifically, there is, for example, a case where an adapter for connection of the memory device 11 is connected to the host device 20 serving as a personal computer. The fifth embodiment enables data transfer between the host device 20 and extension function section 19 of the memory device 11 even when such an adapter is connected to the host device 20.

FIG. 53 schematically shows an example of a case where an adapter 100 serving as, for example, a connection device of the universal serial bus (USB) type is connected between the host device 20 and memory device 11.

The adapter 100 includes a converter 101. The converter 101 includes a command separating section 102, response combining section 103, and command issuing section 104.

FIG. 54 and FIG. 55 show the processing operations of the example shown in FIG. 53. FIG. 54 shows an example of a data write operation, and FIG. 55 shows an example of a data read operation.

When the memory device 11 is connected to the host device 20 by using the USB type adapter 100, a message called a command block wrapper (CBW) is first transmitted from the host device 20 to the adapter 100 and, then transmission or reception of data is carried out. Finally, a message called a command status wrapper (CSW) is transmitted from the adapter 100 to the host device 20 to thereby control transmission/reception of data. A direction of transmission/reception of data, and length of data to be transmitted/received can be specified in the CBW.

In the host device 20, when long data is transferred to the extension function section 19 of the memory device 11, the above-mentioned command header 20 a, and command payload 20 b are used and, when long data is transferred from the extension function section 19 to the host device 20, the response header 20 c, and response payload 20 d are used.

As shown in FIG. 54, at the time of data write, the host device 20 transmits the CBW to the converter 101 (S101). The converter 101 analyzes the CBW, and can learn that data is to be written after this, and can also learn a length of the data to be transmitted thereto (S102). At this time, it is possible to determine on the basis of the length of the data whether or not a command payload is included in the data.

Upon receipt of the command header 20 a, and command payload 20 b transferred from the host device 20 (5103), the converter 101 separates the command header 20 a, and command payload 20 b from each other by using the command separating section 102. That is, the command separating section 102 regards the first 512-byte of the transferred data as the command header 20 a, and regards the subsequent data as the command payload 20 b to thereby separate them from each other. When the length of the data does not exceed 512 bytes, the converter 101 carries out processing assuming that there is no command payload.

The command issuing section 104 issues CMD49 to the command header 20 a supplied from the command separating section 102 (S104), receives a response R1 from the memory device 11 (S105) and, thereafter transfers the command header 20 a to the memory device 11 by using CMD49 (S106). The internal operation (S107) of the memory device is as described above.

Further, the command issuing section 104 issues CMD59 to the command payload 20 b supplied from the command separating section 102 (S108), receives a response R1 from the memory device 11 (S109) and, thereafter transfers the command payload 20 b to the memory device 11 (S110). The memory device 11 processes the command payload (S111).

At the time of issuing CMD59, “BUS” and “BUC” are set in such a manner that their length becomes longer than or equal to the length of the command payload. When “BUS” and “BUC” are set in such a manner that the length becomes longer than the length of the command payload, arbitrary data of a length set by “BUS” and “BUC” may subsequently be transmitted after transmitting the command payload or the processing may be advanced to the next operation by issuing a command to stop the transmission.

After transmitting the data to the memory device 11, the converter 101 transmits a CSW to the host device 20 (S112). Thereby, the host device 20 can learn that the processing of the converter 101 has been completed.

On the other hand, as shown in FIG. 55, when long data is read from the memory device 11, a CBW is transmitted from the host device 20 to the converter 101 (S121). The converter analyzes the CBW, and can learn that data read is to be carried out after this, and can further learn a length of the data to be read (S122). At this time, it is possible to determine from the length of the data whether or not a response payload is necessary. If the length of the specified data exceeds 512 bytes, it is determined that read of a response payload is necessary.

When read of a response payload is necessary, the command issuing section 104 of the converter 101 issues CMD58 (S123). At the time of issuing CMD58, “BUS” and “BUC” are set in such a manner that their length becomes longer than or equal to the length of the response payload. When “BUS” and “BUC” are set in such a manner that the length becomes longer than the length of the response payload, arbitrary data having a length set by “BUS” and “BUC” may subsequently be read after reception of the response payload is finished or the processing may be advanced to the next operation by issuing a command to stop the transmission.

After receiving a response R1 from the memory device 11 (S124), the command issuing section 104 supplies the block received from the memory device 11 to the response combining section 103 (S125).

After this, the command issuing section 104 issues CMD48 (S126). After receiving a response R1 from the memory device (S127), the command issuing section 104 supplies 512-byte data supplied from the memory device 11 to the response combining section 103 as a response header 20 c (S128).

The response combining section 103 combines the response header 20 c, and a response payload 20 d constituted of a plurality of blocks together, and transfers the combined resultant to the host device 20 (S129).

Finally, the converter 101 transmits a CSW to the host device 20 (S130). Thereby, the host device can learn that the converter 101 has completed the processing.

When the command separating section 102 and response combining section 103 are not provided with a work area of a size sufficient for carrying out processing, it is also possible to send the data accumulated so far in the work area to the command issuing section and host device 20 at times to thereby carry out serial processing.

It should be noted that although the above description is that of a case where long data is transferred, in a case of dater transfer where a command payload 20 b and response payload 20 d are not used, the command separating section of the converter 101 simply outputs a command header 20 a, and the response combining section 103 simply outputs a response header 20 c.

Further, the memory device 11 takes time-out (for example, 250 msec) after transmitting necessary data. After this, it may be indicated that transmission of the response payload has been completed by using an event of a response R1.

FIG. 56 is a view showing a modification example of the fifth embodiment, and shows another example of the adapter.

In FIG. 56, an adapter 110 makes it possible to connect the memory device 11 and, for example, a hard disk 113 to the host device 20.

The adapter includes a distributor 111, converter 101, and bridge circuit 112. A first terminal of the distributor 111 is connected to the host device 20 through the USB. A second terminal of the distributor 111 is connected to the memory device 11 through the converter 101. The configuration of the converter 101 is as described above. A third terminal of the distributor 111 is connected to the hard disk 113 through the bridge circuit 112, and a serial ATA (SATA) cable 114. The bridge circuit 112 includes, for example, a memory interface module, memory control module, and the like which are not shown.

Even in the case of such a configuration, it is possible to transfer data between the host device 20 and extension function section 19 of the memory device 11 by using the converter 101.

According to the fifth embodiment described above, even when the adapter 100 is provided between the host device 20 and memory device 11, it is possible to transfer data between the host device 20 and extension function section 19 of the memory device 11 by providing the converter 101 in the adapter 100.

It should be noted that in the above embodiment, as examples of the extension function, there are a security function to be implemented in the controller, and security function to be implemented in a memory such as a NAND flash memory.

The security function to be implemented in the controller implies a function or the like used to store, for example, key information, and identification information or the like unique to the controller in the controller, and configure a communication channel between the controller and host device on the basis of these information items.

Further, the security function to be implemented in a memory implies a function or the like configured to store, for example, key information, identification information unique to the memory, and encrypted identification information created by encrypting the identification information, in the memory, and carry out authentication processing between the memory and host device through the controller on the basis of these information items.

The nonvolatile semiconductor memory device or the nonvolatile memory is not limited to this, and it may be another non-transitory medium.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. 

What is claimed is:
 1. A memory system capable of extending a function, comprising: a memory; and a controller configured to control the memory, wherein the controller generates an extension register provided with a certain block length capable of defining an extension of the function, the controller processes a first command to write header data of a command to extend the function through the extension register, and a second command to read header data of a response through the extension register.
 2. The system according to claim 1, further comprising an extension function section to be controlled by the controller and having the function, wherein the controller processes a third command to write variable-length command data to the extension function section, and a fourth command to read variable-length response data from the extension function section.
 3. The system according to claim 2, wherein the third command comprises a field configured to specify a block size and a block number of the variable-length command data, and the fourth command comprises a field configured to specify a block size and a block number of the variable-length response data.
 4. The system according to claim 2, wherein the header data of the command includes an operation code configured to operate the extension function section, an argument, an argument length indicating a length of the argument, and a command data length indicating a length of the variable-length command data.
 5. The system according to claim 2, wherein the header data of the response includes a response code, response data, and a response data length indicating a length of the response data.
 6. The system according to claim 2, wherein upon receipt of one of the first to fourth commands, the memory device returns a response, and the response includes a first flag indicating that an event has occurred in the extension function section.
 7. The system according to claim 6, wherein the extension register includes a second flag indicating the extension function section in which an event has occurred.
 8. The system according to claim 2, further comprising a converter, wherein the converter includes: a separating section configured to separate the header data and the variable-length command data of the command transferred from a host device from each other; and a command issuing section configured to issue the first command to the header data of the command separated by the separating section, and issue the third command to the variable-length command data.
 9. The system according to claim 8, wherein the command issuing section issues the second command to read header data of a response from the extension function section, and issues the fourth command to read the variable-length response data from the extension function section, and the converter further includes a combining section configured to combine the read header data of the response, and the variable-length response data together, and transfer the resultant data to the host device.
 10. The system according to claim 1, wherein the extension register comprises: a first port configured to transfer the header data of the command; a second port configured to transfer a header of the response; a third port configured to transfer the variable-length command data; and a fourth port configured to transfer the variable-length response data. 